Effects of E-plane Misalignment on THz Diagonal Horn

Paper in proceeding, 2024

E-plane misalignment of split-blocks due to machining tolerances has a detrimental impact on diagonal horn antenna's performance at supra-THz frequencies (>3 THz). To investigate this, a scaled-down version of the diagonal horn, considering cases with and without alignment errors, was characterized around 400 GHz in a near-field measurement setup. The resulting radiation pattern aligned closely with simulated outcomes. Notably, a 6% misalignment relative to the free-space wavelength led to an increased cross-polar component, causing a reduction in the power coupled to a single linear-polarized fundamental Gaussian mode from 84% to approximately 74%.